/* F07FJ_P0W_F C++ Header Example Program.
 *
 * Copyright 2022 Numerical Algorithms Group.
 * Mark 28.4, 2022.
 */

#include <iostream>
#include <nag.h>
#include <nagad.h>
#include <nagx04.h>
#include <stdio.h>
#include <string>
using namespace std;

int main()
{
  int               exit_status = 0;
  nag::ad::handle_t ad_handle;
  Integer           ifail = 0;

  cout << "F07FJ_P0W_F C++ Header Example Program Results\n\n";
  // Skip heading in data file
  string mystr;
  getline(cin, mystr);

  // Read problem size and number of right-hand-sides
  Integer n;
  cin >> n;

  // Allocate arrays containing A and its factorized form, B
  // and the solution X.
  double *a = 0;
  a         = new double[n * n];

  // Read the lower triangular matrix A, register and copy
  double dd;
  for (int i = 0; i < n; ++i)
  {
    for (int j = 0; j <= i; ++j)
    {
      int k = i + j * n;
      cin >> a[k];
    }
  }

  // Factorize the matrix A
  ifail = 0;
  nag::ad::f07fd(ad_handle, "L", n, a, n, ifail);

  // Get the inverse of A
  ifail = 0;
  nag::ad::f07fj(ad_handle, "L", n, a, n, ifail);

  // Print inverse
  cout << endl;
  NagError fail;
  INIT_FAIL(fail);
  x04cac(Nag_ColMajor, Nag_LowerMatrix, Nag_NonUnitDiag, n, n, a, n,
         "  Inverse", 0, &fail);

  delete[] a;
  return exit_status;
}